diff --git a/src/mito2/src/cache/write_cache.rs b/src/mito2/src/cache/write_cache.rs
index d16bc186fe..b464e366cb 100644
--- a/src/mito2/src/cache/write_cache.rs
+++ b/src/mito2/src/cache/write_cache.rs
@@ -26,7 +26,7 @@ use store_api::storage::RegionId;
 use tokio::sync::mpsc::{UnboundedSender, unbounded_channel};
 
 use crate::access_layer::{
-    FilePathProvider, Metrics, RegionFilePathFactory, SstInfoArray, SstWriteRequest,
+    FilePathProvider, Metrics, OperationType, RegionFilePathFactory, SstInfoArray, SstWriteRequest,
     TempFileCleaner, WriteCachePathProvider, WriteType, new_fs_cache_store,
 };
 use crate::cache::file_cache::{FileCache, FileCacheRef, FileType, IndexKey, IndexValue};
@@ -45,7 +45,12 @@ use crate::sst::{DEFAULT_WRITE_BUFFER_SIZE, DEFAULT_WRITE_CONCURRENCY};
 /// Wraps the remote object store used by write cache uploads.
 pub trait WriteCacheUploadStoreWrapper: Send + Sync {
     /// Wraps an object store before uploading a cached file.
-    fn wrap(&self, store: ObjectStore) -> ObjectStore;
+    ///
+    /// `op_type` identifies the origin of the upload so implementations can
+    /// apply different policies per operation, e.g. throttling compaction
+    /// uploads but not flush uploads. Index rebuild uploads are reported as
+    /// [`OperationType::Compact`].
+    fn wrap(&self, store: ObjectStore, op_type: OperationType) -> ObjectStore;
 }
 
 pub type WriteCacheUploadStoreWrapperRef = Arc<dyn WriteCacheUploadStoreWrapper>;
@@ -205,7 +210,13 @@ impl WriteCache {
             .build_sst_file_path(region_file_id);
 
         if let Err(e) = self
-            .upload(parquet_key, &remote_path, &upload_request.remote_store)
+            .upload(
+                parquet_key,
+                &remote_path,
+                &upload_request.remote_store,
+                // `put_and_upload_sst` is only used by the flush path.
+                OperationType::Flush,
+            )
             .await
         {
             // Clean up cache on failure
@@ -292,6 +303,7 @@ impl WriteCache {
 
         let mut upload_tracker = UploadTracker::new(region_id);
         let mut err = None;
+        let op_type = write_request.op_type;
         let remote_store = &upload_request.remote_store;
         for sst in &sst_info {
             let parquet_key = IndexKey::new(region_id, sst.file_id, FileType::Parquet);
@@ -299,7 +311,10 @@ impl WriteCache {
                 .dest_path_provider
                 .build_sst_file_path(RegionFileId::new(region_id, sst.file_id));
             let start = Instant::now();
-            if let Err(e) = self.upload(parquet_key, &parquet_path, remote_store).await {
+            if let Err(e) = self
+                .upload(parquet_key, &parquet_path, remote_store, op_type)
+                .await
+            {
                 err = Some(e);
                 break;
             }
@@ -312,7 +327,10 @@ impl WriteCache {
                     .dest_path_provider
                     .build_index_file_path(RegionFileId::new(region_id, sst.file_id));
                 let start = Instant::now();
-                if let Err(e) = self.upload(puffin_key, &puffin_path, remote_store).await {
+                if let Err(e) = self
+                    .upload(puffin_key, &puffin_path, remote_store, op_type)
+                    .await
+                {
                     err = Some(e);
                     break;
                 }
@@ -381,6 +399,7 @@ impl WriteCache {
         index_key: IndexKey,
         upload_path: &str,
         remote_store: &ObjectStore,
+        op_type: OperationType,
     ) -> Result<()> {
         let region_id = index_key.region_id;
         let file_id = index_key.file_id;
@@ -406,7 +425,7 @@ impl WriteCache {
 
         let upload_store = self.upload_store_wrapper.as_ref().map_or_else(
             || remote_store.clone(),
-            |wrapper| wrapper.wrap(remote_store.clone()),
+            |wrapper| wrapper.wrap(remote_store.clone(), op_type),
         );
         let mut writer = upload_store
             .writer_with(upload_path)
@@ -528,6 +547,8 @@ impl UploadTracker {
 
 #[cfg(test)]
 mod tests {
+    use std::sync::Mutex;
+
     use bytes::Bytes;
     use common_test_util::temp_dir::create_temp_dir;
     use object_store::services::Memory;
@@ -553,10 +574,12 @@ mod tests {
 
     struct RedirectUploadStoreWrapper {
         target_store: ObjectStore,
+        last_op_type: Mutex<Option<OperationType>>,
     }
 
     impl WriteCacheUploadStoreWrapper for RedirectUploadStoreWrapper {
-        fn wrap(&self, _store: ObjectStore) -> ObjectStore {
+        fn wrap(&self, _store: ObjectStore, op_type: OperationType) -> ObjectStore {
+            *self.last_op_type.lock().unwrap() = Some(op_type);
             self.target_store.clone()
         }
     }
@@ -569,6 +592,7 @@ mod tests {
         let target_store = ObjectStore::new(Memory::default()).unwrap().finish();
         let wrapper = Arc::new(RedirectUploadStoreWrapper {
             target_store: target_store.clone(),
+            last_op_type: Mutex::new(None),
         });
         let write_cache = WriteCache::new(
             local_store.clone(),
@@ -593,10 +617,15 @@ mod tests {
         local_store.write(&cache_path, data.clone()).await.unwrap();
 
         write_cache
-            .upload(key, upload_path, &original_store)
+            .upload(key, upload_path, &original_store, OperationType::Compact)
             .await
             .unwrap();
 
+        assert_eq!(
+            *wrapper.last_op_type.lock().unwrap(),
+            Some(OperationType::Compact)
+        );
+
         assert!(original_store.stat(upload_path).await.is_err());
         assert_eq!(
             target_store.read(upload_path).await.unwrap().to_vec(),
diff --git a/src/mito2/src/sst/index.rs b/src/mito2/src/sst/index.rs
index db7089c201..6b26cf5255 100644
--- a/src/mito2/src/sst/index.rs
+++ b/src/mito2/src/sst/index.rs
@@ -1015,7 +1015,14 @@ impl IndexBuildTask {
             )
             .build_index_file_path_with_version(index_id);
             if let Err(e) = write_cache
-                .upload(puffin_key, &puffin_path, remote_store)
+                // Index rebuild is background maintenance work, so its uploads
+                // are reported as compaction uploads.
+                .upload(
+                    puffin_key,
+                    &puffin_path,
+                    remote_store,
+                    OperationType::Compact,
+                )
                 .await
             {
                 err = Some(e);